Correction: An earlier version of this article about a Northern Virginia state Senate race stated that when Sen. Dave Marsden first ran for the seat in a January 2010 special election, he left his wife and children in their home just outside the 37th Senate District and rented a part of a home inside the district. In fact, Marsden's children were grown and already out of the house. This version has been corrected.

Across the Potomac from hyper-partisan Washington, a Northern Virginia Republican running for state Senate counts Bill Clinton, of all people, as his political mentor.

Jason Flanary, a former Marine who said he was stationed at Camp David for two years, said the former president once let him in on some of his campaign-trail strategy.

“President Clinton sat me down and said, ‘Jason, I want to share with you one of the secrets of my success,’ ” Flanary recalled. “ ‘Forty percent of the people will vote against you because of your party ID, 40 percent will vote for you because of your party ID and the 20 percent in the middle, they care first and foremost — are you a nice person? Do you understand and are you talking about the issues that impact their daily lives? And can you relate to them? If you can do those three things, you can win any election.’ ”

As he seeks to unseat Democratic Sen. Dave Marsden in the 37th Senate District, Flanary said the pragmatic centrism Clinton preached will help him woo voters in the Fairfax County swing district.

“It’s about solutions, ideas,” said Flanary, 32. “It’s absolutely an issues-driven district. It’s as purple as you can get.”

Marsden, elected in a January 2010 special election after Ken Cuccinelli II (R) moved up to Virginia attorney general, casts himself in equally nonpartisan terms. He led the state Department of Juvenile Justice under both Republican and Democratic governors. He said he’s worked well with Gov. Robert F. McDonnell (R) and Republican lawmakers on many issues, including transportation and the budget.

“I think it’s good we have a divided legislature in Virginia,” said Marsden, 63. “Everybody keeps an eye on everybody else, and when we sit down and work things out, usually it’s a pretty viable solution. . . . Especially given what’s going on on Capitol Hill, Virginia is working very, very well.”

Sounds like post-partisan nirvana, here in the middle of a race that will help determine whether Democrats hang on to their slim majority in the Senate or if Republicans, who already hold the governor’s mansion and House, gain control.

Both candidates name education, transportation and job creation as top priorities. They offer similar-sounding solutions for some problems. Both want any budget surpluses, or a portion of them, set aside for education. Both say solving the region’s worst-in-the-nation traffic congestion will take road improvements and mass transit. Both say the state has to keeps its budget under control and stimulate job growth.

But both also suggest, in highly partisan terms, that his opponent cannot be trusted.

Marsden claims the purported Clinton protégéreally takes his cues from Grover Norquist, president of Americans for Tax Reform, while Flanary characterizes the incumbent as a big-spending Democrat masquerading as fiscal moderate.

“In terms of transportation, my opponent has signed the no-tax pledge, Grover Norquist’s no-tax pledge, and yet he wants to pay for all these transportation projects,” Marsden said.

On Aug. 21, two days before the Republican primary, Americans for Tax Reform announced that Flanary had signed its “Taxpayer Protection Pledge,” something the anti-tax activist Norquist has pressed on politicians nationwide.

Flanary said he told the group that he would not sign the pledge because he believed that would prevent him from restructuring the tax code, even in a “revenue-neutral” way. But in an Aug. 19 letter to the organization, he said he would oppose “any and all efforts to increase taxes that are not revenue-neutral.” He used the word “promise” instead of “pledge.”

In a phone interview, Norquist said he took Flanary’s promise to mean the same thing as pledge. Flanary said there is a difference.

“Here’s the difference: the folks who go in and sign the pledge — and they have a previously prepared pledge they want candidates to sign — and that provides people with zero maneuverability,” Flanary said. “I have never signed a tax pledge.”

Being taken for a Norquist devotee might not play well in the general election, at least not in a swing district that went 54 percent for McDonnell in 2009 but 57 percent for Barack Obama in 2008.

But Flanary would like to be seen as the more fiscally conservative candidate in the race. He questions Marsden’s campaign promises to hold the line on taxes and cut wasteful spending.

“In the worst economy since the Great Depression, Dave voted to spend $350 million of taxpayer dollars to build a new General Assembly Building,” Flanary said, referring to a plan eventually scuttled by Republicans. (The price tag on the building, dubbed the “Taj Mahal” actually was $300 million.)

Marsden maintains that asbestos in the General Assembly Building threatens the health of employees and visitors.

Democrats redrew the Senate district to favor the party in general and Marsden in particular. Marsden lived just outside the district when the seat came open. He rented the lower level of a house inside the district and said he was living there, though his wife stayed behind. The residency issue was resolved when lines were redrawn under redistricting to include Marsden’s old house, but some observers think the “carpetbagger” charge could stick.

“In the public’s mind, he’s one of those politicians who will do anything to get elected,” said Chris Spanos, a Richmond lobbyist.

Flanary had his own ethics questioned in news reports related to his work as a campaign consultant for Morgan Morris, who in 2003 ran for delegate in the 6th District. A radio ad for Morris was copied from a spot created for the Wisconsin Education Association, with a comment from Morris simply tacked on the end, The Roanoke Times & World News reported at the time.

Morris told the newspaper that Flanary was responsible and that he no longer worked for him. Flanary was not quoted back then. Today, he blames Morris, noting that shortly after the copied radio ad came to light, news surfaced that Morris had been convicted in 1989 of making a threatening phone call to his estranged wife.

“Here’s the sad thing,” Flanary said. “Dave Marsden has chosen to take the word of Morgan Morris, who was convicted of threatening kill his ex-wife, than me, a decorated Marine whose job was to guard the president of the United States.”

Flanary plays up his Camp David service as he goes door-knocking. A Marine from 1997 until 2001, he said he was stationed at the presidential retreat from 1998 to 2000. (Maj. Shawn Haney, a Marines public affairs officer, could not confirm Flanary’s Camp David service but said he had received a presidential service badge, which is consistent with that sort of posting.)

Whenever Clinton and family visited Camp David, Flanary said it was his job to see that their recreational needs were fulfilled. When the president lifted weights , Flanary said he’d spot him. When Clinton jogged, Flanary said he’d stand by with a towel and water. He said he taught Chelsea Clinton to shoot skeet.

“It was a pretty unbelievable experience for a 19- and 20-year-old guy,” said Flanary, who laughed off a suggestion that he hit Clinton up for an endorsement.

Marsden has been favored to win the race because of his huge fundraising advantage. The senator had raised $264,576 as of the last reporting period, compared to $85,724 for Flanary.

“That shows the [Republican] party isn’t putting much money into it,” said Bob Roberts, a James Madison University political scientist.

Yet some observers think Fairfax County’s well-educated, upper-middle class and increasingly worried electorate could be in the mood for change.

“They are [ticked off] at Obama, ticked off at Republicans and Democrats,” Spanos said. “They’re worried about their jobs whether they’re a civil servant or a contractor — either way, they’re going to be laying people off.”